The invention relates to a self-mixing expendable.
The idea of introducing a simulated Doppler shift on expendables through electronic means is to confuse hostile radar operations. The basic approach is to use high frequency electronic switches (i.e. pin diodes) to change the impedance of the expendable antenna. With this arrangement, a frequency shift will be incorporated in the reflected radar signals. This frequency shift will confuse the radar operation as a Doppler frequency shift. This arrangement requires all the components including an antenna, electronic switches, oscillators and power supply be put on the expendable.
The following U.S. Patents are of interest:
U.S. Pat. No. 3,108,275 Chisholm PA1 U.S. Pat. No. 4,445,793 Gibbs PA1 U.S. Pat. No. 4,676,534 Eddy PA1 U.S. Pat. No. 4,733,236 Matosian
Chisholm shows in FIG. 1 a frequency shift reflection system comprising a horn antenna 1, a diode 3, and a single transistor drive oscillator 4. The transistor has a positive feedback circuit connected between its collector and base. Gibbs discusses the deployment of chaff (radar countermeasure dipoles) or other expendable materials from a moving aircraft. Eddy describes a radar target simulator and contains in column 2 a discussion of several prior art patents in this area. A discussion of prior art patents also appear in column 2 of Matosian which is directed to a multispectral reflecting target.